Detection circuit for amplitude modulated signals

Details Detection circuit for amplitude modulated signals Detection circuit for amplitude modulated signals

1990-09-25

1992-06-30

Pascal, Robert J.

Demodulators

Amplitude modulation demodulator

Including three or more terminal discrete semiconductor...

307350, H03D 100

Patent

active

051266830

ABSTRACT:
A detection circuit of amplitude modulated signals comprises a first bipolar transistor having a base connected to an input terminal, a collector connected to a first voltage source providing a first power voltage and an emitter; a second bipolar transistor having a base, a collector connected to the first voltage source, and an emitter which is coupled commonly to the emitter of the first bipolar transistor; an output terminal connected commonly to the emitter of the first bipolar transistor and the emitter of the second bipolar transistor for providing an output signal; a biasing circuit connected to the base of the first bipolar transistor and to the base of the second bipolar transistor for biasing the first and second bipolar transistor; a control circuit having an input terminal connected to the base of the first bipolar transistor for producing a control signal in response to an amplitude modulated signal supplied to the input terminal; and a variable current source having a first end connected to the emitters of the first and second bipolar transistors, and a second end connected to a second voltage source providing a second power voltage which is different from the first power voltage, for causing to flow therethrough a drive current to the second voltage source, wherein the control circuit contols the variable current source by the control signal such that the output signal at the output terminal has a voltage level which increases linearly with increasing amplitude of the input amplitude modulated signal in one of positive and negative half cycles of the amplitude modulated signal and such that the output signal has a constant voltage level in the other of the positive and negative half cycles of the amplitude modulated signal.

REFERENCES:
patent: 4250457 (1981-02-01), Hofmann
patent: 4492926 (1985-01-01), Kusakabe et al.
Patent Abstracts of Japan, vol. 2, No. 56 (E-78) [1385], 24th Apr. 1978 & JP-A-53 020 760 (MATSUSHITA) 25-02-1978.
Patent Abstracts of Japan, vol. 1, No. 98 (E-77) [2864], 31st Aug. 1977; & JP-A-52 031 644 (HITACHI SEISAKUSHO K.K.) 03-10-1977.
Proceedings of the IEEE, vol. 67, No. 4, Apr. 1979, pages 687-689, New York, US; S. Pookaiyaudom et al.: "A Single-Transistor full-wave rectifier".

Affiliated with

Also associated with

Rating

Detection circuit for amplitude modulated signals does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Detection circuit for amplitude modulated signals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Detection circuit for amplitude modulated signals will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1866524